Regular nanocluster networks on Pb/Si(111)-Pb√3X√3 at low temperatures -: art. no. 205406

We have observed the formation of highly regular networks of Pb clusters, which extend up to 100 nm in linear size, during the growth of Pb on the Si(111)-Pbalpharoot3x root3 phase at low temperatures 115 K<T<250 K. The cluster networks are a metastable phase before the first preferred height of two-step Pb islands form as a result of quantum size effects. The cluster networks provide an easy kinetic pathway for the buildup of the two-step islands. The driving force for the formation of the cluster networks is most likely the long range elastic interaction between the Pb atoms mediated through the strained substrate.